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The purpose of this research is to develop a time-cost optimization model to schedule repetitive projects while considering limited resource availability.

The model is based on the constraint programming (CP) framework; it integrates multiple scheduling characteristics of repetitive activities such as continuous or fragmented execution, atypical activities and coexistence of different modes in an activity. To improve project performance while avoiding inefficient hiring and firing conditions, the strategy of bidirectional acceleration is presented and implemented, which requires keeping regular changes in the execution modes between successive subactivities in the same activity.

Two case studies involving a real residential building construction project and a hotel refurbishing project are used to demonstrate the application of the proposed model based on four different scenarios. The results show that (1) the CP model has great advantages in terms of solving speed and solution quality than its equivalent mathematical model, (2) higher project performance can be obtained compared to using previously developed models and (3) the model can be easily replicated or even modified to enable multicrew implementation.

The original contribution of this research is presenting a novel CP-based repetitive scheduling optimization model to solve the multimode resource-constrained time-cost tradeoff problem of repetitive projects. The model has the capability of minimizing the project total cost that is composed of direct costs, indirect costs, early completion incentives and late completion penalties.

This work aimed at studying the use of capillary forces as a gripping principle in the handling of sub‐millimetric sized components. The goal was to present the results as design rules of so‐called capillary grippers.

Each parameter (surrounding environment, materials, volume of liquid, separation distance, gripper geometry and gripper size, relative orientation of the gripper with respect to the component) has been quantified, either numerically or experimentally. In some validation cases, both means have been used.

The capillary forces can be modified between a maximum F_max and a minimum F_min so that a component with any mass m between F_min/g and F_max/g can be picked up and released.

By comparison with some existing capillary grippers prototypes, this work is only a theoretical and experimental study. Nevertheless, its originality lies in the exhaustive study and quantification of all parameters so that most of the capillary grippers of the literature can be explained or improved with these results.

The main implication of the capillary gripping is that it provides an alternative to existing gripping principles (vacuum grippers, tweezers). This principle is strong enough (a few mN) and well adapted to pick up components with only one free accessible surface. The scaling laws are the most favorable (F∼L). It provides a “soft” picking, avoiding high contact forces.

The originality lies in the exhaustive quantification of the role of each parameter. These results can be used by researchers and designers.

Beijing rail transit can actively control the density of rail transit passenger flow, ensure travel facilities and provide a safe and comfortable riding atmosphere for rail transit passengers during the epidemic. The purpose of this paper is to efficiently monitor the flow of rail passengers, the first method is to regulate the flow of passengers by means of a coordinated connection between the stations of the railway line; the second method is to objectively distribute the inbound traffic quotas between stations to achieve the aim of accurate and reasonable control according to the actual number of people entering the station.

This paper analyzes the rules of rail transit passenger flow and updates the passenger flow prediction model in time according to the characteristics of passenger flow during the epidemic to solve the above-mentioned problems. Big data system analysis restores and refines the time and space distribution of the finely expected passenger flow and the train service plan of each route. Get information on the passenger travel chain from arriving, boarding, transferring, getting off and leaving, as well as the full load rate of each train.

A series of digital flow control models, based on the time and space composition of passengers on trains with congested sections, has been designed and developed to scientifically calculate the number of passengers entering the station and provide an operational basis for operating companies to accurately control flow.

This study can analyze the section where the highest full load occurs, the composition of passengers in this section and when and where passengers board the train, based on the measured train full load rate data. Then, this paper combines the full load rate control index to perform reverse deduction to calculate the inbound volume time-sharing indicators of each station and redistribute the time-sharing indicators for each station according to the actual situation of the inbound volume of each line during the epidemic. Finally, form the specified full load rate index digital time-sharing passenger flow control scheme.

The purpose of this research is to study the extent to which various price and earnings momentum measures can be used to enhance portfolio performance by better timing entry into value stocks (and isolating those growth stocks that still have some period to run).

The paper uses the traditional methodology of ranking stocks on the basis of certain value and momentum measures (e.g. book‐to‐market, market return over some prior period), forming portfolios based on these rankings which are held for a specific period of time. The portfolios are formed on the basis of a single measure of multiple measures and the returns and associated p‐values are calculated with the objective of determining how these portfolios perform relative to a benchmark portfolio composed of all the companies in the universe. The analysis is conducted on a database consisting of approximately 8,000 companies drawn from 15 European countries over the period from January 1989 to May 2004.

It was found that a number of individual, and combinations of, price and earnings momentum factors are able to enhance value portfolios by identifying stocks that will not perform well in the immediate future. The best measure that was found for timing entry into value and growth stocks is a combination of price momentum and price acceleration where the difference in monthly performance between the “best” and “worst” value (growth) portfolios is 2.6 percent (2.4 percent) for holding periods of 12 months. It was found not only that this momentum measure can be used to enhance value and growth in portfolios consisting of all European stocks but also that it can be successfully deployed in the major individual markets and regions.

Most studies that evaluate the performance of value and growth portfolios do not consider the characteristics of the stocks held in these portfolios. However, it is these characteristics that determine the success of the portfolios formed on the basis of what can only be described as very crude valuation multiples. This paper demonstrates the potential of a closer evaluation of the stocks chosen to be included in a particular portfolio by being able to identify those stocks most likely to perform (and under‐perform). The findings in the paper have obvious implications for the investment processes of investment managers but they also provide useful insights into the efficiency of the European markets and the typical means of price formation within those markets.

Contemporary stochastic optimal control by synergy of the probability density evolution method (PDEM) and conventional optimal controller exhibits less capability to guarantee economical energy consumption versus control efficacy when non-stationary stochastic excitations drive hysteretic structures. In this regard, a novel multiscale stochastic optimal controller is invented based on the wavelet transform and the PDEM.

For a representative point, a conventional control law is decomposed into sub-control laws by deploying the multiresolution analysis. Then, the sub-control laws are classified into two generic control laws using resonant and non-resonant bands. Both frequency bands are established by employing actual natural frequency(ies) of structure, making computed efforts depend on actual structural properties and time-frequency effect of non-stationary stochastic excitations. Gain matrices in both bands are then acquired by a probabilistic criterion pertaining to system second-order statistics assessment. A multi-degree-of-freedom hysteretic structure driven by non-stationary and non-Gaussian stochastic ground accelerations is numerically studied, in which three distortion scenarios describing uncertainties in structural properties are considered.

Time-frequency-dependent gain matrices sophisticatedly address non-stationary stochastic excitations, providing efficient ways to independently suppress vibrations between resonant and non-resonant bands. Wavelet level, natural frequency(ies), and ratio of control forces in both bands influence the scheme’s outcomes. Presented approach outperforms existing approach in ensuring trade-off under uncertainty and randomness in system and excitations.

Presented control law generates control efforts relying upon resonant and non-resonant bands, and deploys actual structural properties. Cost-function weights and probabilistic criterion are promisingly developed, achieving cost-effectiveness of energy demand versus controlled structural performance.

The purpose of this paper is to define the process of analog circuit optimization on the basis of the control theory application. This approach produces many different strategies of optimization and determines the problem of searching of the best strategy in sense of minimal computer time. The determining of the best strategy of optimization and a searching of possible structure of this strategy with a minimal computer time is a principal aim of this work.

Different kinds of strategies for circuit optimization have been evaluated from the point of view of operations’ number. The generalized methodology for the optimization of analog circuit was formulated by means of the optimum control theory. The main equations for this methodology were elaborated. These equations include the special control functions that are introduced artificially. This approach generalizes the problem and generates an infinite number of different strategies of optimization. A problem of construction of the best algorithm of optimization is defined as a typical problem of the control theory. Numerical results show the possibility of application of this approach for optimization of electronic circuits and demonstrate the efficiency and perspective of the proposed methodology.

Examples show that the better optimization strategies that are appeared in limits of developed approach have a significant time gain with respect to the traditional strategy. The time gain increases when the size and the complexity of the optimized circuit are increasing. An additional acceleration effect was used to improve the properties of presented optimization process.

The obtained results show the perspectives of new approach for circuit optimization. A large set of various strategies of circuit optimization serves as a basis for searching the better strategies with a minimum computer time. The gain in processor time for the best strategy reaches till several thousands in comparison with traditional approach.

The purpose of this paper is to present a novel strategy used for acceleration of free-vibration analysis, in which the hierarchical matrices structure and Compute Unified Device Architecture (CUDA) platform is applied to improve the performance of the traditional dual reciprocity boundary element method (DRBEM).

The DRBEM is applied in forming integral equation to reduce complexity. In the procedure of optimization computation, ℋ-Matrices are introduced by applying adaptive cross-approximation method. At the same time, this paper proposes a high-efficiency parallel algorithm using CUDA and the counterpart of the serial effective algorithm in ℋ-Matrices for inverse arithmetic operation.

The analysis for free-vibration could achieve impressive time and space efficiency by introducing hierarchical matrices technique. Although the serial algorithm based on ℋ-Matrices could obtain fair performance for complex inversion operation, the CUDA parallel algorithm would further double the efficiency. Without much loss in accuracy according to the examination of the numerical example, the relative error appeared in approximation process can be fixed by increasing degrees of freedoms or introducing certain amount of internal points.

The paper proposes a novel effective strategy to improve computational efficiency and decrease memory consumption of free-vibration problems. ℋ-Matrices structure and parallel operation based on CUDA are introduced in traditional DRBEM.

The starting hesitation of a switched reluctance motor (SRM) is an issue which must be considered in the early motor design. It is mostly handled as a control concern. The starting procedure of a SRM using a single Hall-effect position sensor is analysed in this paper. This low cost position measurement solution requires a specific control strategy. That has been developed for a three-phase 6/4 SRM. The paper aims to discuss these issues.

The starting procedure begins with a rotor alignment step intending to bring the rotor to a known position. Afterward, only one phase is supplied on a periodic basis, to drive the rotor in the desired direction and accelerate up to a predefined speed threshold. Thus, the proposed procedure drastically simplifies the control strategy and permits a low cost sensor based control. 2D finite elements simulations are performed to analyse the starting performances in terms of response time and power efficiency. Both electrical and mechanical transients are considered in the simulation model thanks to simplifying assumption which consists in applying a time averaged voltages instead of instantaneous switching. Finally, the entire starting procedure with a one phase supply procedure is tested experimentally.

A starting procedure of a three-phase SRM is implemented. The control effectiveness is validated by complementary FE calculations and measurements.

The starting hesitation issue of a three-phase SRM is solved with an easy control strategy. During the acceleration phase, only one phase is self-controlled.

Since the Great Financial Crisis (GFC), the shocks are getting deeper and deeper on the economy, sectors and companies. In these years, turnaround strategies have evolved and contribute to improving the agility and audacity of managers. This article studies the change in the research agenda and in the academic discourse as systemic disruptions become widespread and provides evidence on collaboration networks and publication opportunities.

This research uses a comparative bibliometric analysis to understand the changes in the academic debate as of 2008. The core collection of Web of Science (WoS) is used and 198 articles on turnaround strategies published in journals indexed in Journal Citation Reports® (JCR) – Social Sciences Citation Index (SSCI) in areas like business, management, economics and finance during 1965–2022.

This research reveals an important intertemporal evolution between periods, both in the collaborative networks of researchers and in the journals that dominate the impact discourse. In addition, it provides evidence of the change in academic discourse, through the evolution of the topics of interest after the GFC. The results suggest publication opportunities around gaps not yet closed by the academic literature.

This article allows researchers to be guided in identifying gaps that have not yet been closed. In addition, this research has important managerial implications, since it guides and advises journal editors on new emerging issues.

This document offers a global vision on the subject of study and an understanding of the development of the discourse of the academy.

This article contributes to the debate by arguing that addressing the core concept underpinning accelerationism and helps to unpack a number of key assumptions on the nature of capitalism, identifying areas offering new and productive insights into organisation and organisations. The scope of the article will be to examine the accelerationist literature, in particular, the core principles first emerging in the prehistory of accelerationism and further developed through the various waves and iterations of the concept.

The paper offers a conceptual approach to accelerationism. It develops a critical literature review and uses a process of exemplification to highlight insights for organisation and organisations.

The paper concludes that the underpinnings of accelerationism are not well understood and thus much of the critique misses the more intriguing and interesting insights from the cluster of ideas at its core.

The scope of the paper is to provide a coherent and accessible way to navigate through a complex and demanding series of concepts. The value of the paper is that it helps to identify potential insights relevant to management, marketing and organisational scholars.